package work;
class Base {
    public int a;
    public Base(int a){
        this.a = a;
    }
    Base() {
        System.out.print("Base");
    }
}

public class Alpha extends Base {

    public static void main( String[] args ) {
        new Alpha();//1
        //调用父类无参的构造方法
        new Base();//2
    }
}